TM-9-2320-280-20 HMMWV Technical Manual Unit Maintenance Volume 1 Download
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REFERENCE INFORMATION If you hear a hissing noise while removing the fuel filter cap then either the vent filter is plugged, the vent line is restricted, or the vent valve is restricted. The vent filter is located behind the coolant surge tank. Replace vent lines or vent line filter, refer to (para. 3-27.) Replace vent valve, refer to (para. 3-24.) Diesel fuel is sensitive to temperature. All diesel fuel has a certain amount of paraffin-like components which have high energy value and help improve fuel economy. When temperatures are less than 20°F (-7°C) these components begin turning into wax flakes that can build upon the fuel tank strainer or in the fuel filter. If wax build-up is found, replace the fuel in the tank with a winter grade of fuel if available. You will have to remove the fuel tank if you need to inspect the tank strainer. Replace fuel tank, refer to (para. 3-24.) TM 9-2320-280-20-1 FUEL SYSTEM 2-113